- Copy stable/10@296371 to releng/10.3 in preparation for 10.3-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.3.
- Update default pkg(8) configuration to use the quarterly branch.

Approved by: re (implicit)

MFC r270882, r270930:

In ARM asm code, ensure that every ENTRY(foo) has a matching END(foo).
The EABI unwind info requires a .fnend for every .fnstart, and newer
binutils will complain about seeing two .fnstart in a row. This change
allows newer tools to compile our code.

Do not generate unwind info in asm functions if _STANDALONE is defined.
The .fnend op causes the assembler to emit RELOC references to unwind
support functions that don't exist in libstand.

Approved by: re(gjb)

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Fix sbrk.S to use _end symbol the same way brk.s was fixed some time
ago. sbrk.S should have gotten the same change then but was forgotten.

Approved by: re (bmah)
PR: kern/114049

Use the RET macro.
For setjmp() and longjmp(), put the signal mask where it's supposed to be,
instead of in the space reserved for fp regs.

Import the FreeBSD/arm libc bits.

Obtained from: NetBSD